A zookeeper at a Nigerian university has been killed by one of the lions he had been looking after for close to a decade.

Olabode Olawuyi, who was in charge of the zoo at Obafemi Awolowo University (OAU), was attacked as he was feeding the lions, the university said in a statement.

His colleagues were unable to save him as one of the lions had already fatally wounded him, the university added.

The lion has since been put down.

Mr Olawuyi, a veterinary technologist, had been "taking care of the lions since they were born on campus about nine years ago".

"But, tragically, the male lion killed the man who had been feeding them," the university's spokesman, Abiodun Olarewaju, said.

"We never knew what came over the male lion that it had to attack [him]," he added.

Nigerians on social media have been sharing graphic images of the mauling at the university in Osun state in the south-west.

The university community is in mourning, and a delegation has gone to the family of Mr Olawuyi to offer their condolences.

The university's vice-chancellor, Prof Adebayo Simeon Bamire, said he was "saddened" by the incident and ordered a thorough investigation.

The students' union leader, Abbas Akinremi, told Nigeria's Vanguard newspaper that the attack was caused by "human error" after the zookeeper had forgotten to lock the door after feeding the lions.

He described the incident as unfortunate while paying tribute to Mr Olawuyi as a "good and humble man, who attended to us nicely whenever we went to the zoo".

Abba Gandu, who has been feeding lions for more than 50 years at a zoo in Kano in northern Nigeria, described Monday's incident as unfortunate and said more safety measures were needed.

"This incident wouldn't in any way affect me personally as feeding lions is what I want to do until I die," said Mr Gandu, who started feeding lions in 1971.

He added that his worst experience was when a baboon he was trying to feed bit his finger.